actinium
Kelime Anlamı :
1. aktinyum.
2. aktinyum (Ac).
3. Aktinyum, Ac, sembolü ile bilinen, atom no: 89 ve atom ağırlığı: 227 olan kimyasal element. (uranyum cevherinde bulunan radyoaktif bir element).
4. (isim) aktinyum.
Tanımlar :
1.
A radioactive element found in uranium ores, used in equilibrium with its decay products as a source of alpha rays. its longest lived isotope is ac 227 with a half-life of 21.6 years. atomic number 89; melting point 1,050°C; boiling point (estimated) 3,200°C; specific gravity (calculated) 10.07; valence 3. see table at element.
from The American Heritage® Dictionary of the English Language, 4th Edition
1.
a radioactive, metallic chemical element (symbol: ac) with an atomic number of 89; found in uranium ores
from Wiktionary, Creative Commons Attribution/Share-Alike License
1.
A supposed metal, said by Phipson to be contained in commercial zinc; -- so called because certain of its compounds are darkened by exposure to light.
from the GNU version of the Collaborative International Dictionary of English
1.
A supposed chemical element found associated with zinc. its chemical and physical properties have not been fully investigated.
2.
3. A radioactive substance found by Debierne to exist in the residues remaining from pitchblende after the extraction of the uranium: a new radio-element closely related in its chemical behavior to lanthanum, from which it has not as yet been found possible to separate it completely.
2.
3. A radioactive substance found by Debierne to exist in the residues remaining from pitchblende after the extraction of the uranium: a new radio-element closely related in its chemical behavior to lanthanum, from which it has not as yet been found possible to separate it completely.
from The Century Dictionary and Cyclopedia